It may sound strange and unlogical, but sometimes
when I have a very full schedule, I can really look
forward to being in a waiting room; the doctor's office, the dentist, waiting
at the hairdresser's...

Why? Because they are drawing opportunities!

Here's what happened when I made the sketch above: My
bangs were almost hanging in front of my eyes, so I went to the
hairdresser. Thinking about how they sometimes have pretty long waiting
times, when it's a busy day.

So
I started just randomly drawing one of the chairs, hoping to add
details of it, and of the interior. But just after a few minutes, I was
already called for my hair cut. So I just left it, and later I added a
little bit of hatching and some background decoration with grey brush
pen, to make the page a little less 'bare'.